Modular air cooled condenser apparatus and method

ABSTRACT

The present invention relates to a mechanical draft cooling tower that employs air cooled condenser modules. The aforementioned cooling tower operates by mechanical draft and achieves the exchange of heat between two fluids such as atmospheric air, ordinarily, and another fluid which is usually steam. The aforementioned cooling tower utilizes a modular air cooled condenser concept wherein the air cooled condensers utilize heat exchange deltas that use tube bundles that are manufactured and assembled prior to being shipped to the tower site.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority and is a continuation of U.S. patentapplication entitled Modular Air Cooled Condenser Apparatus and Method,filed May 23, 2012, having a Ser. No. 13/478,827, the disclosure ofwhich is hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to a mechanical draft cooling tower thatutilizes air cooled condenser modules. The aforementioned cooling toweroperates by mechanical draft and achieves the exchange of heat betweentwo fluids such as atmospheric air, ordinarily, and another fluid whichis usually steam or some sort of industrial process fluid. Theaforementioned cooling tower operates by mechanical draft which utilizesan air current generator such as a fan or the like.

BACKGROUND OF THE INVENTION

Cooling towers are heat exchangers of a type widely used to emanate lowgrade heat to the atmosphere and are typically utilized in electricitygeneration, air conditioning installations and the like. In a mechanicaldraft cooling tower for the aforementioned applications, airflow isinduced or forced via an air flow generator such as a driven impeller,driven fan or the like. Cooling towers may be wet or dry. Dry coolingtowers can be either “direct dry,” in which steam is directly condensedby air passing over a heat exchange medium containing the steam or an“indirect dry” type cooling towers, in which the steam first passesthrough a surface condenser cooled by a fluid and this warmed fluid issent to a cooling tower heat exchanger where the fluid remains isolatedfrom the air, similar to an automobile radiator. Dry cooling has theadvantage of no evaporative water losses. Both types of dry coolingtowers dissipate heat by conduction and convection and both types arepresently in use. Wet cooling towers provide direct air contact to afluid being cooled. Wet cooling towers benefit from the latent heat ofvaporization which provides for very efficient heat transfer but at theexpense of evaporating a small percentage of the circulating fluid.

To accomplish the required direct dry cooling the condenser typicallyrequires a large surface area to dissipate the thermal energy in the gasor steam and oftentimes may present several challenges to the designengineer. It sometimes can be difficult to efficiently and effectivelydirect the steam to all the inner surface areas of the condenser becauseof non-uniformity in the delivery of the steam due to system ductingpressure losses and velocity distribution. Therefore, uniform steamdistribution is desirable in air cooled condensers and is critical foroptimum performance. Another challenge or drawback is, while it isdesirable to provide a large surface area, steam side pressure drop maybe generated thus increasing turbine back pressure and consequentlyreducing efficiency of the power plant. Therefore it is desirous to havea condenser with a strategic layout of ducting and condenser surfacesthat allows for an even distribution of steam throughout the condenser,that reduces back pressure, while permitting a maximum of coolingairflow throughout and across the condenser surfaces.

Another drawback to the current air cooled condenser towers is that theyare typically very labor intensive in their assembly at the job site.The assembly of such towers oftentimes requires a dedicated labor force,investing a large amount of hours. Accordingly, such assembly is laborintensive requiring a large amount of time and therefore can be costly.Accordingly, it is desirable and more efficient to assemble as much ofthe tower structure at the manufacturing plant or facility, prior toshipping it to the installation site.

It is well known in the art that improving cooling tower performance(i.e. the ability to extract an increased quantity of waste heat in agiven surface) can lead to improved overall efficiency of a steamplant's conversion of heat to electric power and/or to increases inpower output in particular conditions. Moreover, cost-effective methodsof manufacture and assembly also improve the overall efficiency ofcooling towers in terms of cost-effectiveness of manufacture andoperation. Accordingly, it is desirable for cooling tower that areefficient in both in the heat exchange properties and assembly. Thepresent invention addresses this desire.

Therefore it would desirous to have an economical, mechanical draft,modular cooling tower that is efficient not only in its heat exchangeproperties but also in its time required for assembly and cost for doingthe same.

SUMMARY OF THE INVENTION

Embodiments of the present invention advantageously provides for afluid, usually steam and method for a modular mechanical draft coolingtower for condensing said steam.

An embodiment of the invention includes a method for assembling amodular air cooled condenser extending along a vertical axis away fromhorizontal, comprising the steps of: assembling a first condenser bundleassembly having a first set of tubes having first and second ends, asteam manifold connected to the first ends of the tubes, and acondensate header connected to the second ends of the tubes; assemblinga second condenser bundle having a second set of tubes having first andsecond ends, a steam manifold connected to the first ends of the tubes,and a condensate header connected to the second ends of the tubes;placing the first and second condenser bundle assemblies in to acarrier; transporting the carrier to a location upon which the modularair cooled condenser will be assembled; assembling a heat exchange deltaby placing the first condenser bundle and the second condenser bundle;and positioning the heat exchange delta on a modular tower frame.

Another embodiment of the present invention includes a modular aircooled condenser extending along a vertical axis away from horizontal,comprising: means for assembling a first condenser bundle assemblyhaving a first set of tubes having first and second ends, a steammanifold connected to the first ends of the tubes, and a condensateheader connected to the second ends of the tubes; means for assembling asecond condenser bundle assembly having a second set of tubes havingfirst and second ends, a steam manifold connected to the first end ofthe tubes, and a condensate header connected to the second ends of thetubes; means for placing the first and second condenser bundleassemblies in to a carrier; means for transporting the carrier to alocation upon which the modular air cooled condenser will be assembled;means for assembling a heat exchange delta by placing using the firstcondenser bundle and the second condenser bundle; and means forpositioning the heat exchange delta on a modular tower frame.

Another embodiment of the present invention, A mechanical draft modularair cooled condenser that cools an industrial fluid is disclosed,comprising: a plenum with which at least one delta resides wherein saidat least one delta comprises first condenser bundle having a first setof tubes having first and second ends, a steam manifold connected to thefirst ends of the tubes, and a condensate header connected to the secondends of the tubes; and a second condenser bundle having a second set oftubes having first and second ends, a steam manifold connected to thefirst ends of the tubes, and a condensate header connected to the secondends of the tubes; a support frame that supports said plenum; and ashroud that houses an air current generator.

In yet another embodiment of the present invention, a method forassembling a modular air cooled condenser extending along a verticalaxis is disclosed, comprising: assembling a first condenser bundlehaving a first set of tubes having first and second ends and acondensate header connected to the second end of the tubes; assembling asecond condenser bundle having a second set of tubes having first andsecond ends, and a condensate header connected to the second end of thetubes; placing the first and second condenser bundles in to a carrier;transporting the carrier to a location upon which the modular air cooledcondenser will be assembled; assembling a heat exchange delta by placingusing the first condenser bundle and the second condenser bundle; andpositioning the heat exchange delta on a modular tower frame.

There has thus been outlined, rather broadly, certain embodiments of theinvention in order that the detailed description thereof herein may bebetter understood, and in order that the present contribution to the artmay be better appreciated. There are, of course, additional embodimentsof the invention that will be described below and which will form thesubject matter of the claims appended hereto.

In this respect, before explaining at least one embodiment of theinvention in detail, it is to be understood that the invention is notlimited in its application to the details of construction and to thearrangements of the components set forth in the following description orillustrated in the drawings. The invention is capable of embodiments inaddition to those described and of being practiced and carried out invarious ways. Also, it is to be understood that the phraseology andterminology employed herein, as well as the abstract, are for thepurpose of description and should not be regarded as limiting.

As such, those skilled in the art will appreciate that the conceptionupon which this disclosure is based may readily be utilized as a basisfor the designing of other structures, methods and systems for carryingout the several purposes of the present invention. It is important,therefore, that the claims be regarded as including such equivalentconstructions insofar as they do not depart from the spirit and scope ofthe present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned and other features and advantages of thisdisclosure, and the manner of attaining them, will become more apparentand the disclosure itself will be better understood by reference to thefollowing description of various embodiments of the disclosure taken inconjunction with the accompanying figures.

FIG. 1 is a perspective view of an air cooled condenser module inaccordance with an embodiment of the present invention.

FIG. 2 is a schematic side view of the air cooled condenser moduledepicted in FIG. 1 in accordance with an embodiment of the presentinvention.

FIG. 3 is another schematic side view of the air cooled condenser moduledepicted in FIG. 1 in accordance with an embodiment of the presentinvention.

FIG. 4 is a perspective view of an A-type condenser configuration inaccordance with an embodiment of the present invention.

FIG. 5 illustrates the condenser bundles in a packaged arrangement forshipping in accordance with an embodiment of the present invention.

FIG. 6 schematically illustrates the steps of assembly of an air cooledcondenser in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description, reference is made to theaccompanying drawings, which form a part hereof and show by way ofillustration specific embodiments in which the invention may bepracticed. These embodiments are described in sufficient detail toenable those skilled in the art to practice them, and it is to beunderstood that other embodiments may be utilized, and that structural,logical, processing, and electrical changes may be made. It should beappreciated that any list of materials or arrangements of elements isfor example purposes only and is by no means intended to be exhaustive.The progression of processing steps described is an example; however,the sequence of steps is not limited to that set forth herein and may bechanged as is known in the art, with the exception of steps necessarilyoccurring in a certain order.

Turning now to FIG. 1, a modular air cooled condenser module, generallydesignated 10, is illustrated. The air cooled condenser module 10generally includes a plenum 12, having an air current generator or fandisposed within a fan shroud or inlet bell 14 and a plurality of supportcolumns or legs 16. The air cooled condenser module 10 further includesmultiple A-type geometry deltas, each designated 18. Each delta 18comprises two tube bundle assemblies 28 with a series of finned tubes toconduct heat transfer. The deltas 18 will be discussed in further detailbelow.

Turning now to FIGS. 2 and 3, schematic side views of the air cooledcondenser 10 are depicted. As specifically illustrated in FIG. 2, theair cooled condenser employs risers 20 which are welded to the mainsteam duct 22. The risers 20 are connected to a steam manifold 24 whichoperates to keep the steam flow velocity more constant. This abovedescribed configuration is part the A-type condenser bundles 28 that areshipped as a unit from the factory, which will be discussed in furtherdetail below. The condenser bundles 28 are preferably welded to therisers 20 via a transition piece 26 to accommodate the geometry of thesteam manifold.

Turning now to FIG. 4, a delta 18 is illustrated. As depicted, eachdelta 18 is comprised of two individual heat exchange bundle assemblies28, each having a series of finned tubes. The individual tubes areapproximately two (2) meters in length whereas the bundle length isapproximately twelve (12) meters. As illustrated, each bundle assembly28 is positioned at an angle to one another to form the A-typeconfiguration of the delta 18. While the bundle assemblies 28 may bepositioned at any desired angle, they preferably are positioned at anangle approximately twenty degrees (20°) to approximately thirty degrees(30°) from vertical and approximately sixty degrees (60°) toapproximately seventy degrees (70°) from horizontal. More specifically,the bundle assemblies 28 are positioned at twenty-six degrees (26°) fromvertical and sixty-four degrees (64°) from horizontal.

Each of the bundle assemblies 28 are assembled prior to shipping whereineach comprises a riser to header transition piece 26, steam manifold 24,finned tubes 25, and steam condensate headers 27. As can be seen in FIG.1, due to the modular design and orientation of the bundle assemblies28, the air cooled condenser design 10 has approximately five (5) timesmore tubes as compared to typical designs. Moreover, the embodiments ofthe current invention not only utilize five (5) times the tubes, butemploy condenser tubes that are much shorter in length. As result of theaforementioned design and orientation, the steam velocity travelingthrough the tube bundles 28 is reduced as result of the increased numberof tubes in combination with the reduced tube length, and thereforesteam pressure drop within the deltas 18 is reduced, making the air coolcondenser 10 more efficient.

Typically, turbine back pressure of an air cooled condenser or the likeis limited by the maximum steam velocity in the tubes (to limit erosion)wherein the steam velocity is increasing with a decrease of backpressure (due to density of steam). Thus, due to the addition of tubesin accordance with the present invention, the steam is still maintainedat the maximum allowable steam velocity but at a lower back pressure.The other limitation the current delta design addresses is that thepressure at the exit of the secondary bundles cannot be less than thevacuum group capability. This pressure typically results from turbineback pressure minus the pressure drop in ducting minus the pressure dropin the tubes. Accordingly, due to the reduced pressure drop in thetubes, the allowable turbine back pressure is lower with the delta 18design.

Furthermore, the above-described bundle design also reduces the pressuredrop within the individual delta 18. For example, the heat exchange thattakes place via the deltas 18, is dependent upon the heat exchangecoefficient, i.e., the mean temperature difference between air and steamand the exchange surface. Due to the reduced pressure drop as previouslydescribed, the mean pressure (average between inlet pressure and exitpressure) in the exchanger is higher with the design of the currentcondenser configuration 10. In other words, because steam is saturated,the mean steam temperature is also higher for the same heat exchangesurface resulting in increased heat exchange.

Turning now to FIG. 5, a transport carrier, generally designated 30 isillustrated. As the name suggests, the transport container or carrier 30is used to transport the bundles 28, from the factory to the job site.As illustrated, the condenser bundles 28, are manufactured and assembledat the factory with the respective steam manifold 24 and steamcondensate headers 27. While five (5) bundles are illustrated positionedin the transport container or carrier, more or less individual bundlesmay be shipped per carrier depending as needed or required.

Alternatively, the above described embodiments of the present employtube bundles manufactured and assembled, prior to shipping, having steammanifold 24 and steam condensate headers 27, alternative embodimentbundles may not include a manifold prior to shipping. More specifically,in such embodiments, the tube bundles may be ship without steammanifolds 24 attached thereto. In said embodiments, the tube bundles 28may be assembled in field to form the A-type configuration, as discussedabove. However, instead of employing two steam manifolds, thisalternative embodiment may employ a single steam manifold wherein thesingle steam manifold extends along the “apex” of the A configuration.

Referring now to FIG. 6, a flow chart is illustrated, schematicallydepicting the steps of assembly of the air cooled condenser tower 10. Aspreviously described, the individual tube bundles 28 are assembled priorto shipment to the job site, as referenced by numeral 40. Eachindividual bundle assembly 28 includes a plurality of finned tubes 25along with a steam manifold 24 and steam condensate header 27. Aspreviously discussed in connection with the previous figures of thespecification, the bundle assemblies 28 are pre-manufactured at thefactory prior to placing the individual bundle assemblies 28 in theshipping carrier 30 as identified by numeral 42. The shipping carriers30 are then shipped to the erection field site.

Next, the delta, generally indicated as 18, is assembled in the field asidentified by numerals 44 and 46. As previously described, while thebundles may be positioned at any desired angle, they preferably arepositioned at an angle (y) approximately twenty degrees (20°) toapproximately thirty degrees (30°) from vertical and an angle (x)approximately sixty degrees) (60°) to approximately seventy degrees(70°) from horizontal. More specifically, the bundles are positioned attwenty-six degrees (26°) from vertical and sixty-four degrees (64°) fromhorizontal. As designated by numeral 46, a single A-type delta isillustrated 18 formed by two bundle assemblies 28 to form the “A”configuration. The bundle assemblies 28 self support one another in thisconfiguration.

Turning now to the air cooled condenser module 10 as referenced by thenumeral 48, it is depicted employing five deltas 18. As discussed above,the air cooled condenser is an improvement over current air cooledcondenser types and it has a high “pre-fabrication” level which equatesto reduced installation cost and reduced installation time. Moreover,the above-described design reduces the pressure drop, thereby providinga more efficient heat exchange apparatus.

The many features and advantages of the invention are apparent from thedetailed specification, and, thus, it is intended by the appended claimsto cover all such features and advantages of the invention which fallwithin the true spirit and scope of the invention. Further, sincenumerous modifications and variations will readily occur to thoseskilled in the art, it is not desired to limit the invention to theexact construction and operation illustrated and described, for examplea forced draft air cooled condenser has been illustrated but an induceddraft design can be adapted to gain the same benefits and, accordingly,all suitable modifications and equivalents may be resorted to that fallwithin the scope of the invention.

What is claimed is:
 1. A method for assembling a modular air cooledcondenser extending along a vertical axis away from horizontal,comprising: assembling a first condenser bundle having a first set oftubes having first and second ends, and a condensate header connected tothe second ends of the tubes; assembling a second condenser bundlehaving a second set of tubes having first and second ends, and acondensate header connected to the second ends of the tubes; placing thefirst and second condenser bundles in to a carrier; transporting thecarrier to a location upon which the modular air cooled condenser willbe assembled; and assembling a heat exchange delta using the firstcondenser bundle and the second condenser bundle.
 2. The methodaccording to claim 1, further comprising attaching a steam manifold tothe first ends of the of the first and second sets of tubes at thelocation, wherein the steam manifold provides steam to the firstcondenser bundle and the second condenser bundle.
 3. The methodaccording to claim 2, further comprising positioning the heat exchangedelta on a modular tower frame.
 4. The method according to claim 1,wherein the step of assembling the heat exchange bundle comprisesplacing the first condenser bundle at an angle to vertical andhorizontal and placing the second condenser bundle at an angle tovertical and to horizontal wherein the first and second heat exchangebundles contact one another at a point to form an “A” typeconfiguration.
 5. The method according to claim 4, wherein each of thefirst and second heat exchange bundles is positioned at an angle tohorizontal equal to approximately sixty degrees to approximately seventydegrees and wherein each of the first and second heat exchange bundlesis positioned at an angle to vertical equal to approximately twentydegrees to approximately thirty degrees.
 6. The method according toclaim 5, wherein each of the first and second heat exchange bundles ispositioned at an angle to horizontal equal to approximately sixty-fourdegrees and wherein each of the first and second heat exchange bundlesare positioned at an angle to vertical equal to approximately twenty-sixdegrees.
 7. The method according to claim 1, wherein each of the firstand second set of tubes have fins attached thereto.
 8. The methodaccording to claim 1, wherein said set of tubes comprises tubes having alength equal to approximately two meters.
 9. The method according toclaim 8, wherein each of said first and second condenser bundles has alength equal to approximately twelve meters.
 10. The method according toclaim 1, further comprising the steps of: assembling a third condenserbundle having a third set of tubes having first and second ends, and acondensate header connected to the second ends of the third set oftubes; assembling a fourth condenser bundle having a fourth set of tubeshaving first and second ends, and a condensate header connected to thesecond ends of the tubes; and placing the third and fourth condenserbundles into the carrier.
 11. The method according to claim 10, furthercomprising attaching a steam manifold to the first ends of the of thethird and fourth sets of tubes at the location, wherein the steammanifold provides steam to the third condenser bundle and the fourthcondenser bundle.
 12. The method according to claim 11, furthercomprising: assembling a second heat exchange delta by placing using thethird condenser bundle and the fourth condenser bundle; and positioningthe second heat exchange delta on the modular tower frame.
 13. Themethod according to claim 3, wherein the modular tower frame comprises:a plenum within which the delta resides; at least two columns thatsupport the plenum; and a shroud that houses an air current generator.14. The method according to claim 13, wherein the delta is five deltasand the air current generator is a fan.
 15. A modular air cooledcondenser extending along a vertical axis away from horizontal,comprising: means for assembling a first condenser bundle having a firstset of tubes having first and second ends, and a condensate headerconnected to the second ends of the tubes; means for assembling a secondcondenser bundle having a second set of tubes having first and secondends, and a condensate header connected to the second ends of the tubes;means for placing the first and second condenser bundles in to acarrier; means for assembling a heat exchange delta by using the firstcondenser bundle and the second condenser bundle; and means fortransporting the carrier to a location upon which the modular air cooledcondenser will be assembled.
 16. The modular air cooled condenseraccording to claim 15, further comprising a means for attaching a steammanifold to the first ends of the of the first and second sets of tubesat the location, wherein the steam manifold provides steam to the firstcondenser bundle and the second condenser bundle.
 17. The modular aircooled condenser according to claim 15, further comprising a means forpositioning the heat exchange delta on a modular tower frame.
 18. Themodular air cooled condenser according to claim 17, wherein said meansfor assembling the heat exchange bundle comprises a means for placingthe first condenser bundle at an angle to vertical and horizontal and ameans for placing the second condenser bundle at an angle to verticaland to horizontal wherein the first and second heat exchange bundlescontact one another at a point to form an “A” type configuration. 19.The modular air cooled condenser according to claim 18, wherein each ofthe first and second heat exchange bundles is positioned at an angle tohorizontal equal to approximately sixty degrees to approximately seventydegrees and wherein each of the first and second heat exchange bundlesis positioned at an angle to vertical equal to approximately twentydegrees to approximately thirty degrees.
 20. The modular air cooledcondenser according to claim 19, wherein each of the first and secondheat exchange bundles is positioned at an angle to horizontal equal toapproximately sixty-four degrees and wherein each of the first andsecond heat exchange bundles are positioned at an angle to verticalequal to approximately twenty-six degrees.